DNA sequences specifying the transcription of the streptococcal kanamycin resistance gene in Escherichia coli and Bacillus subtilis.

The gene conferring resistance to kanamycin, aphA, and originating from the streptococcal plasmid pJH1 was inserted into a shuttle vector. Full expression of aphA was obtained in Escherichia coli and Bacillus subtilis. The starting point for aphA transcription, determined by S1 nuclease mapping, was located 340 base pairs upstream from the ATG translational initiator codon. The sequence of the promoter consists of the hexanucleotides TTGACA and TATCTT, with a spacing of 17 base pairs. The stability profile of a 600 base-pair-long DNA fragment containing the aphA promoter and the translational initiation site indicated that, as already reported for Escherichia coli, both structures are located in domains of weak stability.